The present invention relates to circular hosiery knitting machines, the methods of knitting employed thereby, and the articles produced thereon and particularly to hosiery articles of the terry-knit cushion sole type and the machines and methods for knitting same.
In the circular knitting of hosiery articles, it is known to knit the foot portion, and sometimes also a part of the leg portion, of a terry knit construction of plated pile and base yarns which produces a thicker fabric having uncut pile loops to provide a cushioning effect when worn, this type of construction generally being referred to as cushion sole construction. Cushion sole construction finds its greatest applicability in the knitting of athletic and similar type socks in which the cushioning effect provided is most desirable and needed. As will be understood, cushion sole knitting is somewhat more costly than ordinary non-plated hosiery knitting operations due to the greater amount and attendant cost of yarn required and the somewhat slower plated knitting process. It is additionally known and desirable to produce contoured heel and toe areas in the foot portions of such athletic socks to enhance the fit and protection to the wearer thereof. Such heel and toe areas are typically knitted conventionally by a reciprocal knitting process wherein, during the knitting of each individual sock, the rotary motion of the needle cylinder of the knitting machine is temporarily interrupted at a selected appropriate time and the cylinder is reciprocated during such time to knit with the needles on one circumferential half thereof thereby to knit partial courses to provide an increased number of courses along one side of the sock to impose a curvature therealong. This operation is also a relatively costly one in that it requires special machine preparation and further is slower than the circular, rotary knitting motion of the needle cylinder.
Recently, athletic socks having no knitted heel or toe contours, generally referred to as "tube" socks, have come into popularity because of the reduction in production and attendant consumer costs which result from the elimination of the reciprocal heel and toe knitting operation. However, as will be understood, a less desirable fit is provided with such tube socks which is only partially compensated by the provision of elasticity in the foot portion thereof.
It is known in the knitting of non-terry hosiery articles to knit contoured portions by rotary knitting through the use of multiple knitting stations at least some of which are arranged to operate to knit on only certain successive needles to form the desired partial courses, but this procedure is not known to have been successfully applied to terry-type cusion sole knitting due to problems in insuring the proper plating of the base and pile yarns when knitting on only certain needles.
In contrast, the present invention provides a novel method and apparatus for knitting contoured heel and toe portions in terry knit cushion sole socks by a rotary rather than reciprocal motion of the needle cylinder which produces contoured portions comparable to reciprocal knitting operations while insuring proper plating, thereby providing significant time and cost savings thereover.